docs: def _buildTemplates(self):
          """
          OVERRIDING THIS METHOD from Factory
          """
  
          c_mylist = build_D3treeStandard(0, 99, 1,
                                          self.ontospy_graph.toplayer_classes)
          p_mylist = build_D3treeStandard(0, 99, 1,
                                          self.ontospy_graph.toplayer_properties)
          s_mylist = build_D3treeStandard(0, 99, 1,
                                          self.ontospy_graph.toplayer_skos)
  
          c_total = len(self.ontospy_graph.all_classes)
          p_total = len(self.ontospy_graph.all_properties)
          s_total = len(self.ontospy_graph.all_skos_concepts)
  
          if False:
              # testing how a single tree would look like
              JSON_DATA_CLASSES = json.dumps({
                  'children': [{
                      'children': c_mylist,
                      'name': 'Classes',
                      'id': "classes"
                  },
                               {
                                   'children': p_mylist,
                                   'name': 'Properties',
                                   'id': "properties"
                               },
                               {
                                   'children': s_mylist,
                                   'name': 'Concepts',
                                   'id': "concepts"
                               }],
                  'name':
                  'Entities',
                  'id':
                  "root"
              })
  
          # hack to make sure that we have a default top level object
          JSON_DATA_CLASSES = json.dumps({
              'children': c_mylist,
              'name': 'owl:Thing',
              'id': "None"
          })
          JSON_DATA_PROPERTIES = json.dumps({
              'children': p_mylist,
              'name': 'Properties',
              'id': "None"
          })
          JSON_DATA_CONCEPTS = json.dumps({
              'children': s_mylist,
              'name': 'Concepts',
              'id': "None"
          })
  
          extra_context = {
              "ontograph": self.ontospy_graph,
              "TOTAL_CLASSES": c_total,
              "TOTAL_PROPERTIES": p_total,
              "TOTAL_CONCEPTS": s_total,
              'JSON_DATA_CLASSES': JSON_DATA_CLASSES,
              'JSON_DATA_PROPERTIES': JSON_DATA_PROPERTIES,
              'JSON_DATA_CONCEPTS': JSON_DATA_CONCEPTS,
          }
  
          # Ontology - MAIN PAGE
          contents = self._renderTemplate(
              "d3/d3tree.html", extraContext=extra_context)
          FILE_NAME = "index.html"
          main_url = self._save2File(contents, FILE_NAME, self.output_path)
  
          return main_url